Repro Session 4 Flashcards
What is the adult remnant of the processus vaginalis in the male?
Tunica vaginalis
What are the two coverings of the testis?
Tunica vaginalis and tunica albuginea
What invaginates the testis and splits it into lobules with fibrous septae?
Tunica albuginea
Describe the descent of the testes.
7 wks: gonads develop retroperitoneally within mesonephric ridge. 7 months: descend through abdomen and cross inguinal canal 8 wks before delivery. 9 months: exit anterolateral abdominal wall taking layers with them
Why might a premature delivery lead to testes outside of the scrotum?
They don’t cross the inguinal canal until 8 weeks before delivery
What gives arterial supply to the testes?
Direct branch of the abdominal aorta, the testicular artery
Where does the venous drainage of the testes empty?
R testicular vein into IVC and L into L renal vein
What are the three components of the epididymis?
Head, body and tail
How does the epididymis connect to seminiferous tubules?
Via effect tubules ductules and rete testis
Describe the path of the spermatid cord.
Deep inguinal ring, lateral to inferior epigastric vessels via inguinal canal and superficial inguinal ring to posterior border of testis
What are the contents of the spermatic cord?
Testicular artery, cremastic artery, artery to vas, pampiniform plexus, genital branch of genitofemoral nerve, vas deferens, lymphatics and processus vaginalis
How does the pampiniform plexus aid spermatogenesis?
Veins forming it wrap around arteries to reduce blood temperature
What covering of the spermatic cord does the external abdominal oblique aponeurosis form?
External spermatic fascia
What forms the cremasteric muscle and fascia in the spermatic cord?
Internal abdominal oblique and transversalis fascia
What forms the internal spermatic fascia in the spermatic cord?
Transversalis fascia
What is the order of spermatic cord coverings from superficial to deep?
External spermatids fascia, cremasteric muscle and fascia, internal soermatic fascia
Why are indirect inguinal hernias often called congenital despite not presenting at birth?
Have a developmental basis
What is an indirect inguinal hernia?
Reopening of the processus vaginalis creating a potential continuity between the peritoneal cavity and the tunica vaginalis
Where does the spermatic cord usually twist in testicular torsion?
Just above the upper pole of the testis
What gives innervation to the anterior surface of the scrotum and testis?
Lumbar plexus
Where does the sacral plexus give innervation to in the scrotum and testis?
Posterior and inferior surfaces
Where does lymph from the testis drain to?
Paraaortic nodes
Why do the testis not drain to local lymph nodes?
Due to the developmental origin of the testis
Where does lymph from the scrotum drain?
Superficial inguinal nodes
Describe the passage of the ductus deferens.
Ascends in spermatic cord, inguinal canal, pelvic side wall, dilated ampulla, ejaculatory duct
What proportion of the ejaculate volume is secreted by the seminal vesicle?
70-80%
Where is the seminal vesicle positioned?
Retroperitoneal between the bladder and rectum at the diverticulum of vas deferens
What does the combination of the spermatic vesicle and vas deferens ducts form?
Ejaculatory duct
Describe the position of the prostate gland.
Base adjacent to neck of bladder, apex adjacent to urethral sphincter and deep perineal muscles, anterior surface adjacent to urethral sphincter, posterior adjacent to ampulla of rectum and inferolateral adjacent to levator ani
What divides the prostate into anatomical lobes?
Urethra and ejaculatory ducts as they pass through
What are the four anatomical lobes of the prostate gland?
Inferoposterior, inferolateral, superomedial and antero medial
Which anatomical lobes tend to be affected in BPH?
Superomedial and anteromedial
Where is the central zone of the prostate found?
Around ejaculatory ducts
What is the embryological origin of the central zone of the prostate?
Wolffian duct
Where is the transitional zone of the prostate found?
Centrally around the urethra
What is the embryological origin of the transitional and peripheral zones of the prostate?
Urogenital sinus
Where is the peripheral zone of the prostate found?
Forms the main body, located posteriorly
To which nodes might malignancy spread from the peripheral zone of the prostate?
Internal iliac or sacral
Describe the path a metastatic cancer may take in the venous drainage from the peripheral zone of the prostate.
Internal vertebral plexus through the vertebrae to the brain
Which zone of the prostate is examined by DRE?
Peripheral
What type of tissue makes up the prostate gland?
Fibromuscular
What are the three components of the penis?
Root, body and glans
What gives arterial supply to the penis?
Branches of internal pudendal arteries
What are the four parts of the male urethra?
Pre-prostatic, prostatic, membranous and spongy
What does the prostatic urethra receive?
Ejaculatory ducts
Why is the membranous urethra the least distensible portion of the male urethra?
Surrounding fibrous pelvic floor and perineum
What does the distal expansion of the ventral corpus spongiosum form?
Glans penis
What happens to the dorsal pair of corpora cavernosa during erection?
They swell with blood
How does ischiocavernous help maintain erection?
Compresses veins in the root
What does bulbospongiosus help to do in the male?
Expel last drops of urine and with autonomic supply maintains erection
Are ischiocavernosus and bulbospongiosus found in the male and female?
Yes
What are the contents of the labioscrotal folds?
Testis, epididymis, 1st part of spermatic cord
What can cause enlargement of the scrotum?
Inguinal hernia, hydrocoele, haematocoele, varicocoele, epipdidymitis
What is hydrocoele?
Serous fluid in the tunica vaginalis usually due to failure of the processus vaginalis to close
What is haematocoele?
Accumulation of blood in the tunica vaginalis
What is varicocoele?
Dilation of testicular veins
Why is varicocoele usually seen in the left?
Left testicular vein drains into the smaller L renal vein rather than the IVC
How are hydro- and haematocoele differentiated clinically?
Transillumination
What do the scarpa and camper layers of the abdominal wall become in the scrotum?
Darts fascia and muscle
Is the scarpa or camper layer of the SC tissue of the anterior abdominal membranous?
Scarpa
What are the corresponding scrotal coverings of the anterior abdominal wall muscles?
External oblique and its fascia –> external spermatic fascia. Internal oblique –> cremaster muscle. Fascia of superficial and deep internal obliques –> cremasteric fascia. Transversalis fascia –> internal spermatic fascia
What does the peritoneum become in the scrotum?
Tunica vaginalis
What gives the rugose appearance of the scrotum?
Smooth muscle fibres of dartos muscle
How does the dartos muscle help reduce heat loss when the scrotum is exposed to cold air?
Fibres contract causing scrotum to wrinkle. This thickens the integumentary layer, decreases surface area and helps the cremaster muscle to hold the testes closer to the body
What gives arterial supply to the scrotum?
Posterior scrotal branches of perineal artery (internal pudendal), anterior scrotal branches of deep external pudendal artery (femoral) and cremasteric artery (inferior epigastric)
What accompanies the arteries in the scrotum?
Scrotal veins
What suspends the testes in the scrotum?
Spermatic cord
Which testis is usually more inferior?
Left
What is the sinus of epididymis?
Slit-like recess of tunica vaginalis between the body of epididymis and posterolateral testis
What is the mediastinum of testis?
Thickened ridge of tunic albuginea on the internal posterior aspect of the testes that gives rise to fibrous septae that split the gonad info lobules
What are the rete testis?
Network of canals in the mediastinum of the testis
Describe the venous drainage from the testes to the IVC/ L renal vein.
Arise from testis and epididymis, into pampiniform plexus that converges superiorly to R and L testicular veins
Describe the passage of the testicular arteries.
Arise from anterolateral AA just inferior to renal artery and move retroperitoneally crossing the ureters, moving inferior to external iliac artery through the inguinal canal into the spermatic cord
What do the testicular arteries anastomose with?
Artery of ductus deferens
What forms the thermoregulatory system of the testes?
Pampiniform plexus, cremasteric muscle and dartos muscle
What gives autonomic innervation to the testes?
Testicular plexus of nerves on the testicular artery
What is epipdidymitis?
Inflammation of the epididymis usually due to bacterial or viral infection
Describe the passage of sperm through the epididymis.
Rete testis, efferent ductules, duct, head, body and tail of epididymis
Describe the structure of the duct of epididymis.
Appears solid due to tightly compacted convolutions. Gets smaller from head to tail
What happens to sperm in the duct of epididymis?
Stored and mature
Describe the structure of the head of epididymis.
12-14 efferent ductules coiled ends form lobules in the superior extended part
Describe the structure of the body of epididymis.
Major part of structure with tightly convoluted duct of epididymis
What is the tapering tail of epididymis continuous with to transport sperm to the ejaculatory duct for expulsion?
Ductus deferens
What gives innervation to the epididymis?
Autonomic and sensory fibres from the renal and aortic plexus via the testicular plexus
What gives arterial supply to the epididymis?
Testicular arteries
What gives venous drainage to the epididymis?
Pampiniform plexus
Where does lymph from the epididymis drain?
Lumbar and pre aortic nodes at L1
Which structures in the male reproductive tract derive from the mesonephric duct?
Seminal vesicles, Ejaculatory ducts, Epididymis and Ductus deferens (SEED)
What innervates the loops of striated cremaster muscle in the spermatic cord?
Genital branch of genitofemoral nerve (L1&2) from the lumbar plexus
What happens in the cremasteric reflex?
Stroking the superior medial thigh causes elevation of the testis on that side
What is tested when assessing the cremasteric reflex?
Afferent ilioinguinal/genitofemoral nerve and efferent genital branch of genitofemoral
Where does the artery of ductus deferens arise from?
Inferior vesical artery
Where are the nerve fibres found in the spermatids cord?
Sympathetic on arteries and sympathetic and parasympathetic on ductus deferens
How can the vestige of processus vaginalis be identified?
Fibrous thread anteriorly extending between abdominal peritoneum and tunica vaginalis
What would severe and sudden pain in one or both testes following exercise indicate?
Testicular torsion
How is testicular torsion investigated?
US or colour Doppler
What are the layers of muscle found in the vas deferens?
Inner longitudinal, intermediate circular and outer longitudinal smooth muscle
What is the ductus deferens?
45 cm long straight muscular tube that conducts sperm from epididymis to ejaculatory duct
Why do the ductus deferens require a rich autonomic supply?
For peristalsis
Where does lymph from the vas deferens drain?
External and internal iliac nodes
Describe the passage of the vas deferens.
Tail of epididymis, inguinal canal, lateral pelvic wall close to ischial spines, turns medially to pass between bladder and urethra and forms ejaculatory duct with seminal vesicle
Where are the seminal vesicles found?
Between bladder fundus and rectum
What separates the seminal vesicles from the rectum superiorly and inferiorly?
Superiorly: retro vesicle pouch
Inferiorly: retro vesicle septum
Describe the structure of the seminal vesicles.
Honeycombed, lobulated structure with pseudostratified so lumbar epithelium
What happens to the epithelium of the seminal vesicles with higher levels of testosterone?
Grows taller
What is the function of the seminal vesicles?
Secrete 70% of the volume of the ejaculate and play a key role in its normal function
What are the components of the seminal vesicle secretions?
Alkaline fluid, fructose, prostaglandins and clotting factors
What is the function of the alkaline fluid secret by the seminal vesicle?
Neutralises male urethra and femal vagina for spermatozoa survival
What is the energy source for spermatozoa in the ejaculate?
Fructose
What is the function of the prostaglandins secreted by the seminal vesicle?
Suppress female immune response to foreign semen
What is the function of the clotting factors secreted by the seminal vesicle?
To keep the semen in the female reproductive tract post-ejaculation
What gives arterial supply to the seminal vesicles?
Inferior vesical, internal pudendal and middle rectal arteries
What type of innervation do the seminal vesicles receive?
Sympathetic
Where does lymph from the seminal vesicle drain?
External and internal iliac lymph nodes
What gives venous drainage to the seminal vesicles?
Veins accompanying the supplying arteries
Approximately what size are the seminal vesicles?
5 cm
Describe the passage of structures that join to form the ejaculatory duct that drains into the prostatic urethra.
Seminal gland ducts and ductus deferens near the neck of bladder run anteroinferiorly close together to the posterior prostate, alongside the prostatic utricle to converge on the seminal colliulus
What is found at the seminal colliculus allowing drainage of the ejaculatory ducts?
Tiny slit-like apertures
Do prostatic secretions enter the ejaculatory ducts as it passes through the prostate?
No, not until it terminates in the urethra
What gives arterial supply to the ejaculatory ducts?
Arteries to ductus deferens
What gives venous drainage to the ejaculatory ducts?
Prostatic and vesical venous plexuses
Approximately how long are the ejaculatory ducts?
2.5 cm
Which is the largest accessory gland of the male reproductive tract?
Prostate
What proportion of the ejaculate is secreted by the prostate?
20%
What is the function of the secretions from the prostate in the ejaculate?
Activate sperm
What is the composition of the prostate tissue?
2/3 glandular, 1/3 fibromuscular
What are the two coverings of the prostate?
Fibrous capsule and visceral layer of pelvic fascia (fibrous prostatic sheath)
Describe the fibrous capsule of the prostate.
Dense and neurovascular with prostatic venous and nervous plexuses
Describe the fibrous prostatic sheath.
Thin anteriorly, continuous with puboprostatic ligaments anterolaterally and thick posteriorly where it blends with the retrovesical septum
Describe the isthmus of the prostate.
(Anterior lobe) fibromuscular anterior to urethra, a continuation of the EUS to the bladder neck
Why do the superomedial and anteromedial lobes of the prostate undergo hormone-induced hypertrophy in old age?
Due to embryonic median lobe origin
What gives innervation to the prostate?
Inferior hypogastric plexus
What gives arterial supply to the prostate?
Prostatic arteries, branches of internal iliac and pudendal arteries and middle rectal arteries
What gives venous drainage to the prostate?
Prostatic venous plexus that drains into internal iliac veins that communicate with vesical and internal vertebral plexuses
What separates the anterior aspect of the prostate gland from the pubic symphysis?
Retroperitoneal fat
What is felt on DRE in prostatic malignancy?
Hard and irregular tissue
What increases the risk of cystitis and kidney damage in BPH?
Straining
How can DRE be used to assess an abscess rupture that has caused pus to enter the peritoneal cavity?
If bladder is moderately full it can be palpated and massaged to release secretions that can be tested for gonococci
What are the bulbourethral (Cowper) glands?
2 pea side glands that secrete alkaline mucus-like fluid into the urethra during sexual arousal
Describe the path secretions from Cowper’s glands take.
Ducts through perineal membrane into bulb of penis to empty through miniature apertures into proximal spongy urethra
Where are the bulbourethral glands located?
Posterolateral to intermediate urethra, largely embedded in EUS
What gives arterial supply to the bulbourethral glands?
Arteries to the bulb of penis
What gives innervation to the bulbourethral glands?
Autonomic fibres from the prostatic plexus
Where does lymph drain to from the bulbourethral glands?
Internal and eternal iliac nodes
Which nerve roots are involved in the erectile bodies of the penis?
S2&3
What do the presynaptic sympathetic fibres from T12-L2/3 supply in the male reproductive tract?
Components of lumbar splanchnic nerves and hypogastric and pelvic plexuses
What do the presynaptic parasympathetic fibres from S2&3 give rise to in the male reproductive tract?
Pelvic splanchnic nerves and prostatic nerve plexus
What does sympathetic stimulation cause in the male orgasm?
Contraction of IUS, persistaltic-like contractions of vas deferens and combined contraction and secretion from seminal glands and prostate
Which two muscles form levator ani?
Pubococcygeus and iliococcygeus
Which muscles form the pelvic diaphragm?
Pubococcygeus, iliococcygeus and coccygeus
Which muscles form perineum?
Pubococcygeus, iliococcygeus, coccygeus, bulbospongiosus and ischiocavernosus
Which two muscles of the perineum are more superficial?
Bulbospongiosus and ischiocavernosus
Describe the position of the root of the penis.
Most proximal portion, fixed in superficial perineal pouch of pelvic floor
What does the root of the penis contain?
3 erectile tissues and 2 muscles
What are the 3 erectile tissues found in the root of the penis?
L and R crura and bulb of penis
What separates the L and R crura in the penis?
Septum of penis
What are the crura attached to?
Ischial rami
What traverses the bulb of the penis?
Urethra
Why does the ventral corpus spongiosum fill to a pressure that is lower than that seen in the dorsal corpora cavernosa?
Prevent occlusion of the urethra
What do the L and R crura become in the body of the penis?
Dorsal corpora cavernosa
What does the bulb become in the body of the penis?
Ventral corpus spongiosum
Describe the structure of the body of the penis.
Free part suspended from public symphysis consisting of 3 cylinders of erectile tissue
What forms the conical shape of the gland of the penis?
Distal expansion of corpus spongiosum
What goes the glans of the penis contain?
External urethral orifice
What forms the fundiform ligament?
Condensations of abdominal SC tissue
How does the fundiform ligament support the penis?
Extends from linea Alba, slings around penis and attaches to the pubic symphysis
What forms the suspensory ligament of the penis?
Condensations of the deep fascia of the penis
What are the 2 fascial coverings around each erectile tissue mass in the penis?
Superficially the deep fascia of penis from the deep perineal fascia. Deep to this is the tunica albuginea around each cavernous body
What are the most common aetiologies of erectile dysfunction?
Vascular e.g. Hypertension, hyoercholestrolaemia or psychological e.g. Anxiety, depression
What is priapism?
Erection for >4 hrs without sexual stimulation due to trapping of blood in the erectile bodies
What can result from priapism?
Scarring and erectile dysfunction
How does the suspensory ligament support the erectile bodies of the penis?
Attaches them to the public symphysis
Describe the skin of the penis.
More heavily pigmented, attached to tunica albuginea by loose CT
What is the prepuce?
Double layer of skin and fascia at the neck of the glans that covers it to a variable extent
What connects the prepuce to to the skin of the glans of the penis?
Frenulum-median fold of skin on the ventral aspect of the penis
What is the preputial sac?
Potential space between the glans and prepuce
What gives arterial supply to the penis?
Dorsal and deep arteries of the penis and bulbourethral artery (branches of internal pudendal from anterior internal iliac)
Which arteries of the penis supplies the corpora cavernosa?
Deep arteries of the penis
What gives venous drainage to the penis?
Deep dorsal vein drains cavernous spaces into prostatic venous plexus. Superficial dorsal veins drain skin and cutaneous tissues
Which spinal cord segments give innervation to the penis?
S2-4
What supply do the nerves in the penis give?
Dorsal nerve of penis gives sensory and sympathetic innervation to skin and glans of penis. Cavernous nerves from prostatic nerve plexus give parasympathetic stimulation for vascular changes in erection
What are hypospadias?
Congenital conditions where the urethra opens into the ventral surface of the penis
What is phimosis?
Prepuce is tightly over glans and cannot be retracted causing irritation when smegma accumulates in the preputial sac
What is paraphimosis?
Retraction of prepuce and glans causes constriction of glans neck and obstructing venous and lymph drainage so that glans enlargers and prepuce cannot move over it
What is Peyronie’s disease?
When scar tissue causes abnormal shaft curvature leading to a painful erection
